Spaniard here:

With family adult males, cheek kissing is almost the rule. It is sometimes done with very close or longtime friends. I guess it denotes tight bond.

Handholding between males is only done child- adult ( exception noted of some folk dances).

Arm over shoulder very common among buddies, or drinking partners when sauntering from bar to bar.

Wee keep less interpersonal distance while talking than many cultures, and we usually lightly touch in various non-threatening manners to punctuate or emphasize ( usually the forearm, the upper arm ,or the shoulder)